Steven Haryantohttp://cpanratings.perl.org/dist/File-Which#7640
Rating: 5 stars
You can always count on CPAN to have prewritten modules for various things, including this one. I've never bothered before about portability and just rely on the "which" command, but for one reason there's a time when I just couldn't do that.
Btw, there's also File::Which::Cached.Steven Haryanto